1. Field of the Invention
This invention relates to a system and method for evaporating fluids. More particularly, this invention relates to a system for evaporating wastewater left over from oil or gas drilling, fracturing, and production operations by spraying the water through nozzles located above the surface of a pond away from the pond banks.
2. Description of the Related Art
In oil and gas drilling operations drilling fluid is used to remove the drill cuttings from the bore hole and lubricate the drill. The drilling fluid is usually a mixture of clays, chemicals, weighting material and water. The drilling fluid is pumped down the hollow drill string to the bit where it picks up the drill cuttings, then circulated back up the annular space around the drill string to a drilling mud return line. From the return line the fluid passes across a shaker or screen which catches the larger cuttings while the rest of the drilling mud flows down into a mud pit. From the mud pit the drilling fluid may be sent to a particle separator where most of the remaining solids are separated from the wastewater which is then stored in a wastewater pit.
The problem with this arrangement is that the collected wastewater eventually must be disposed of. Various evaporation systems have been devised to accomplish this task. Typically, these systems involve spraying the water into the air using high-pressure pumps to maximize the surface area in order to enhance evaporation.
These spray evaporation systems have several disadvantages. First, some cannot operate in high winds or extreme cold weather. Second, the mist still allows for ground saturation in some areas of sustained winds which requires system to shut down. Third, these systems can be cumbersome to set up, maintain and move.
Foust U.S. Pat. No. 4,762,276 describes a water evaporation system that includes a floating tank that can float in the middle of a pond, a water collector tank suspended under the floating tank, and riser pipes attached to the collector tank at an angle to carry water from the collector tank to spray nozzles. The Foust system does not have a water tank that is mounted between a pair of floating tanks and risers extending vertically upward from the water tank so that the spray nozzles located at the riser ends are located as far as possible from the pond shore.
Thus there is a need for an improved spray evaporation system useful in oil and gas drilling operations that is easy to set up and tear down, is capable of operating in windy or sub-zero temperatures, and minimizes ground saturation.
Another object of the invention is to maximize the dispersal of large volumes of water by providing water droplets having the maximum available surface area.
Yet another object of the invention is to provide a wastewater remediation system that minimizes impact on the environment, particularly from ground saturation by wastewater.
Further and additional objects will appear from the description, accompanying drawings, and appended claims.